Thanks Jim - I see a 1K Ohm in series for a "point type" ignition in the GRT installation manual but can't find anything in the Rotax installation manual. I have found several postings in a variety of forums from folks with the same problem (worked fine, now, suddenly doesn't) but nothing definitive for a solution. The answers that seem to work are related to different grounding schemes or resistor placement as you suggested. I'd rather try a bunch of these before even thinking about changing out the pick up coil so I'm off to try your suggestion first. Thanks for the response.